JP2014111306A - Apparatus and method for polishing semiconductor dies - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus or polishing method for simultaneously removing layers of material from many semiconductor dies by polishing.SOLUTION: The apparatus comprises a plurality of T-tools or other die holding devices which enable semiconductor dies to be positioned in various orientations. A multi-segmented device 20 for holding a plurality of dies has slots 202, which are open areas. In each slot 202, at least one stop 24 is positioned. The stop 24 can be positioned at a different radial distance from the center of a grinding wheel. In some embodiments, the segments are offset from each other around a template in order to increase an effective working area of a grinding surface.

Description

  This disclosure relates to semiconductor polishing, and more particularly to an apparatus and method for simultaneously removing multiple layers of material from many semiconductor dies without human intervention.

  It is often necessary to grind (polish) a layer of semiconductor so that the internal structure can often be visually inspected by observation using an electron microscope. . An abrasive fixture useful for holding a semiconductor (or other device to be polished) against a polishing wheel for this purpose is the subject of US Pat. No. 5,272,844. It is. Currently, some polishing operations are performed using a positioning structure that is suspended above a grinding wheel. The positioning structure is a frame with an open center and a plurality of openings spaced circumferentially and into which a die holding tool can be inserted. is there. The operator uses the sides of the opening to help stabilize the holding tool while the die is being polished. There is a problem with the positioning device if it is desired to polish the die without requiring the operator to keep working on the tool. These problems are mainly related to the fact that the tool is not firmly held and therefore "was wobbled". A stop is provided for the device to keep the tool in the opening. However, stops have no effect on their intended purpose.

  Such polishing is a manual process that can take from half a day to a few days with the operator standing in front of the polishing wheel and holding the device while the wheel is rotating. The holding device allows the semiconductor to be positioned in various orientations depending on the planar angle at which the holding device is desired to be removed by polishing. Has been built. This procedure is slow and tedious and often leads to hand and finger cramps.

  The simultaneous removal of material layers from many dies without human intervention is the fact that multiple die holding devices are segmented into various segments of a template mounted over a grinding surface. This is achieved by temporarily placing it in the open area (segment). In one embodiment, the frictional force imparted to each holding device by the grinding wheel serves to position the holding device within the boundaries of each opening so as to press against the stop. The stops in each segment can be located at different radial distances from the center of the grinding wheel to polish each of the dies using different portions of the polishing wheel. In some embodiments, the segments are offset around the template to increase the effective working area of the grinding surface.

  The foregoing has outlined rather broadly the elements and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. It should be recognized by those skilled in the art that the disclosed concepts and specific embodiments can be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. is there. It should also be understood by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features believed to be characteristic of the present invention (in terms of both construction and method of operation), together with further objects and advantages, will be better understood from the following description when considered in conjunction with the accompanying figures. Let's go. However, it should be understood that the figures are provided for purposes of illustration and description only and are not intended to define the boundaries of the present invention.

Reference is now made to the following description, taken in conjunction with the accompanying drawings, for a more complete understanding of the invention.
FIG. 1A illustrates a typical multilayer semiconductor. FIG. 1B shows a typical grinder used to polish a semiconductor layer. FIG. 2 shows a top view of one embodiment of a multi-segmented apparatus for holding a plurality of dies during polishing. FIG. 3 is a perspective view of one embodiment of a support structure. FIG. 4 illustrates one embodiment of a flowchart of a method using the polishing support concept detailed herein.

Detailed description

  FIG. 1A illustrates a typical multilayer semiconductor (die), for example, semiconductor die 10. As shown, the die 10 has a passivation layer 101, layers 102, 103, 104, and 105 on which active circuits can be built, and vias 110, 111, and 112. With one or more vias, electrical connections can be constructed to run from one layer to another.

  Defects can occur inside the die during the design and / or manufacturing process. In order for the defect to be able to be improved for the next produced die, the defect must be identified. For example, assume that a malfunction has been detected in the circuit operation of a manufactured die such as die 10. In such a situation, the die 10 is delaminated by polishing the continuous surfaces of the plurality of materials using, for example, a grinder 100 shown in FIG. 1B ( delayered). The surface of the die 10, such as the surface 101, is held in contact with the moving grinding surface 12 of the grinder 100 and over time the surface 101 is removed so that it can be observed, for example, via an electron magnification. Layer 102 is exposed. If it is determined that the layer 102 is not defective, the via 110 is slowly polished away under the monitoring of the via 100 that has been touched by an operator for possible defects. As will be detailed later, the integrated circuit package can be positioned in a tool (T-tool) and the contact angle of the integrated circuit package with respect to the grinding surface 12 is adjusted as desired. It is possible. The tool for holding the die can be any of the known tools for holding the die for polishing, such as is available from TD Jam Precision. These tools have silicon feet that allow the tool to hold a work piece at various angles with respect to the grinding surface. The work target (die) can be fixed to the tool using fasteners, screws, epoxy resins, adhesives, springs, and the like.

  Sometimes defects are pre-isolated into a layer or layers so that it is not necessary to stop processing before reaching these layers. Thus, if a defect is found somewhere in the die 10 between layers 104 and 105 (by electrical testing or otherwise), layers 101-103 are polished away without detailed observation. Will be done. The timing can determine how deep (how many layers) the polishing has gone through.

  In the detailed example, polishing continues, typically using a micron slurry (not shown), until the structure preceding level 130 has been removed (delaminated). Polishing continues with observation being made (eg, every 1/2 micron) after a certain amount has been renewed. Eventually, defect 130 becomes visible and the operator will know that via 111 is shorted to via 112 by defect 120. It is often required to polish several IC devices in this manner to find one or more defects. This can take an entire day (and sometimes even longer) for each IC device, rather than half a day. This process is known in the industry as P (polishing P) lapping.

  FIG. 2 shows a top view of one embodiment of a multi-segmented apparatus (eg, apparatus 20) for holding multiple dies while polishing the dies in parallel. . The device 20 has an outer edge 201 that is designed to mate with the outer periphery of the grinder 100 (142 in FIG. 1). If desired, if the grinder has a physical dimension that differs from the physical dimension of the device 20, an insert (not shown) can be used to adapt the device 20 to a grinder such as the grinder 100 (FIG. 1A). It is. Looking down the open area (“wing”) 202 of the device 20, the surface area 12 of the grinder is visible. The open area has a windmill opening in the illustrated embodiment. In this embodiment, the grinder surface 12 is assumed to rotate or move counterclockwise with respect to the device 20 held stationary by the frame of the grinder 20 (FIG. 1A).

  Located within each slot 202 is at least one stop 24. As will be described in detail later, the stop 24 for each slot 202 is measured outward from the center of the grinder 100 so that the wear on the grinding surface 12 is spaced radially outward. It is possible for the radii to be located at the same radius or preferably at various radii. For a 7 mm die, the stops 24 can be separated from each other by a 7 mm offset.

  In operation, the device to be polished is placed on the bottom surface of the removable tool 26 (not shown in FIG. 2). After the die is installed in the tool 26, the tool 26 is positioned in one of the slots 202 to be pressed against the grinding surface 12. This positioning can be accomplished regardless of whether the grinder 100 is operating or stopped. The frictional force of the moving grinder surface 12 against the substrate forces the tool 26 to hold the substrate (die) against the side walls and the stop 24.

  The tool 26 continues to remain pressed against the stop 24, while the grinder surface 12 rotates under it without requiring the operator to maintain pressure or even contact the tool 26. Using this arrangement, multiple tools 26 (in this embodiment, three other tools) can be located in other slots 202 of the device 20 so that the same grinder 100 can be used. In use, all four dies can be polished at the same time without the need to use an operator's hand to maintain the position of the respective tool 26. Note that the die holding tools 26 need not be the same because each slot 202 operates independently of each other slot 202. Also, although only one tool 26 is described in detail as being capable of being positioned in one slot 202, if the diameter of the grinding surface 12 is large enough to support multiple tools 26, Note that the device 20 can be designed to allow multiple tools 26 to be autonomously placed in each slot 202.

  In one example, staggering the placement of each tool 26 by 7 mm allows the grinding surface 12 to wear uniformly, and the centripetal force moves the slurry away from the center so that the slurry is evenly positioned. Is possible.

  The stop 24 is in a mating relationship with the end of the T tool 26 so as to prevent the tool 26 from wobbling and keep the tool 26 within the boundaries of the slot 202 in which it is placed. Can be designed. In one embodiment, the stop 24 is rounded to fit the end of the T tool 26. In other embodiments, the stop 24 is at a 90 degree angle to the downstream sidewall of the slot 202. The height of the slot side can be adapted to the height of the tool. In one embodiment, this height is 15 mm. Note that the slots 202 are not symmetrical with respect to the center and are offset (shifted) from the symmetrical position by about 17.5 mm, so that the central openings of the slots 202 do not face each other. I want to be. This offset allows the grinder face 12 having a fixed diameter to handle more dies than if the slots 202 were perfectly symmetric with respect to the center of the grinder 100. The actual internal contour of each slot 202 is not critical, but should be designed so that the T tool or other die holding device 26 is easily positioned for both placing and removing within the slot area 202. is there.

  A cover or partial cover can be positioned above each slot 202 as desired. The cover or partial cover can serve as a splash proof to keep the slurry in the cover or dome.

  Note that the tool 26 can be designed with many indentations along the top surface of the T portion. The recess may engage one or more tabs that protrude from the wall 210, thereby holding the tool 26 in a fixed relationship within each slot 202.

  FIG. 3 is a perspective view of one embodiment 30 of a template structure that utilizes the concepts of this disclosure. In the illustrated embodiment, the support (abrasive template) 30 has an outer edge 31 that is designed to be permanently or temporarily attached to the grinder 100. This attachment can be, for example, by a skirt (not shown) around the outer edge of the support, where the hem engages the grinder 100. Also, the attachment of the grinder can be a foot, for example, a foot 32 attached to the grinder 100 to prevent the template 30 from moving while the grinder 100 is moving. Also, the peripheral support can engage the fixed structure of the grinder 100, for example by using fastener friction, notches, velcro, or the like. The top surface 36 can be thought of as a bridge that hangs from the outer edge 31 (and support 32) to cover the grinding surface. In the illustrated embodiment, the surface 36 is relatively horizontal, but the surface 36 covers the slot to help prevent slurry splashing from the grinder surface 12 while the template is being used. May have a portion that curves upwardly above the slots 33-1 to 33-4 to form a partial cover or dome. The template is open in the middle so that the die is placed therein and its holding tool 26 is placed on the grinding surface 12 as detailed above with respect to FIG.

  The template extends to cover the grinding surface 12 and has one or more slots 33-1 to 33-4 that extend radially outward from the central opening toward the outer edge support. Each slot region 33-1 to 33-4 has at least one sidewall 34 extending downward from the center to a point just above the grinding surface 12. The exact distance above the grinding surface 12 where the lower end of the template wall 34 is located is controlled by the height of the skirt (or leg) 32 around the outer edge 31 so that the side wall 34 provides stability to the T tool 26. As long as it has sufficient surface area and height “h”, it is not critical. The side wall 34 is constructed on the downstream side of the slot regions 33-1 to 33-4. The downstream in this situation is the side where the grinding surface 12 moves in the slot regions 33-1 to 33-4. If the grinding surface 12 moves in both directions, it may be necessary to use two sidewalls 34 for an autonomously supporting polishing operation in both directions. In the embodiment of FIG. 2, since the grinding surface 12 is assumed to be counterclockwise, the downstream side of the slot regions 33-1 to 33-4 is on the left side of the slot regions 33-1 to 33-4. Shown as being.

  As detailed above and with reference to FIG. 3, the friction caused by the grinder 100 against the die surface below the T tool 26 is downstream of the side of the T tool 26 (the top surface of the T tool). It presses against the side wall 34 and engages with the stops 35-1 to 35-4 (for example, the stops 35-1 to 35-4) attached on the respective side walls 34. Since the stops 35-1 to 35-4 are positioned closer to the center of the grinding surface 12 than the T tool 26, the movement of the grinder 100 pulls the T tool 26 to press against the stops 35-1 to 35-4. Because the stops 35-1 to 35-35 are designed to mate with at least the sides of the T tool 26 or have at least a complementary structure, the frictional force against the die from the grinding surface 12 causes the T tool 26 to move to the downstream side wall 34 and the stop. Maintain a stable relationship with 35-1 to 35-35.

  When the holding tool 26 is placed in the slots 33-1 to 33-4, the friction holds the tool 26 in place. Then, the operator can freely arrange other dies in the other slot regions 33-1 to 33-4. At any time during the polishing process, any tool 26 can be easily removed while the grinder 100 continues to polish other dies. Thus, the operator can take out any die or return it to its original position at any time without disturbing other dies that remain in position relative to their respective downstream sidewalls 34.

  FIG. 4 illustrates one embodiment of a flowchart 40 of a method for using the polishing support concept detailed herein. Step 401 determines whether there is a die ready for polishing mounted in the holding tool. If not, step 402 allows the die to be attached by the operator or machine selecting the desired orientation of the die to be given with respect to the grinding (polishing) surface.

  Step 403 determines whether the appropriate template is located on the appropriate grinder, and if not, step 404 selects the appropriate template and grinder and attaches the template to the grinder.

  Step 405 then positions the retained die within the open slot of the selected template. The grinder is turned on (if the grinder is not yet on) and the bottom of the located die is polished for a period of time. Polishing results from the grinding surface moving relative to the die surface. As a result, the friction caused by the grinding surface against the die moves the side of the holding tool against the downstream side wall and is in meshing relationship with the stop mounted on the side wall.

  Once step 405 is complete, step 406 determines whether additional dies are available for polishing. If available, steps 401-406 are repeated and the second, third, and fourth tools can be simultaneously located in other slots of the selected template.

  Step 407 determines whether it is time to inspect one of the located dies. This can be done by elapsed time or by some situation with other signals available to the operator. If it is time for inspection, step 408 removes the die from the slot with the grinding surface continuing to move relative to the template support, and the die is inspected.

  Step 409 determines whether polishing has been completed for the inspected die. If completed, the die is not returned to the template. If the polishing has not been completed, the process proceeds to step 405 again. If polishing is complete, step 410 ends polishing for the inspected die. Note that even if one die is removed from the template, the other die will continue to be polished without human intervention.

  Although the invention and its advantages have been described in detail, various changes, substitutions, and changes can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that there is. In addition, the scope of the present application is not intended to be limited to the specific embodiments of the processes, machines, manufacture, configurations, means, methods, and steps described in the specification. Those skilled in the art will appreciate from this disclosure of the present invention that performs substantially the same functions or achieves substantially the same results as the corresponding embodiments presently or later developed and described herein. It will be readily appreciated that a process, machine, manufacture, configuration, means, method, or step can be utilized in accordance with the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, structures, means, methods, or steps.

Although the invention and its advantages have been described in detail, various changes, substitutions, and changes can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that there is. In addition, the scope of the present application is not intended to be limited to the specific embodiments of the processes, machines, manufacture, configurations, means, methods, and steps described in the specification. Those skilled in the art will appreciate from this disclosure of the present invention that performs substantially the same functions or achieves substantially the same results as the corresponding embodiments presently or later developed and described herein. It will be readily appreciated that a process, machine, manufacture, configuration, means, method, or step can be utilized in accordance with the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, structures, means, methods, or steps.
The invention described in the scope of the claims of the present invention is appended below.
[C1]
An apparatus for smooth polishing of at least one die, comprising:
A template for positioning on a polishing surface, wherein the template comprises at least one slot extending radially outward from the center of the template, the slot being used for polishing a die in parallel to the polishing surface. The slot having at least one side wall extending downward from the template toward the grinding surface when the template is arranged to cover the polishing surface. The side wall extends above the polishing surface and the height is at least equal to the height of the tool used to hold the die; and
At least one stop positioned within the contour of the slot, the stop being stationary in the slot and moving to the polishing surface as the polishing surface moves relative to the positioned die. At least one stop that operates to keep it in contact with, and
A device comprising:
[C2]
The fixture is
At least one additional slot extending radially outward from the center of the template, each of the additional slots being offset circumferentially from another of the plurality of slots. More slots,
Further comprising
Each of the further openings is
At least one sidewall extending downward from the template toward the grinding surface when the template is positioned to cover the grinding surface, the wall having a height “h” above the polishing surface. Elongate, the height “h” being at least one side wall at least equal to the height of the tool used to hold the die;
At least one stop located within the contour of the further slot, the stop being stationary in the further slot and moving the polishing surface while the polishing surface is moving relative to the located die. At least one stop that operates to keep it in contact with
Comprising
C1 device.
[C3]
The plurality of stops of each of the further slots are located at different radial distances within the respective openings;
C2 device.
[C4]
The central openings of each of the further slots are not opposite one another,
C2 device.
[C5]
A splash ablation formed to cover the plurality of slots, the splash ablation having an opening in the center of the housing,
A C4 apparatus, further comprising:
[C6]
Die polishing tool support,
An outer edge for temporarily engaging with the grinder;
A template supported by the outer edge portion, wherein the template is held by the outer edge portion above the grinding surface of the grinder with which the outer edge portion is engaged, and the template is an open central portion. portion), and a template
A first slot formed in the template, wherein the slot region extends radially outward from the open central portion toward the outer edge portion, the slot extending from the template above the grinding surface; A first slot having a side wall extending downwardly to a position above the grinder surface that is high enough to inhibit movement of a first die attach tool placed in the first slot. When,
A first stop located on the sidewall at a radius from a center point of the template, the first stop comprising a structure for promoting the suppression of the first tool, wherein the suppression is the first stop; A first stop, partly facilitated by movement of the grinding surface relative to a tool;
Die polishing tool support comprising:
[C7]
A second slot formed in the support, the second slot extending radially outward from the open central portion toward the outer edge portion and horizontally extending from the first slot; The second slot has a side wall portion extending downwardly from the template to a position just above the grinding surface, the side wall of a second die attach tool located in the second slot. A second slot having a height above the grinder surface sufficient to inhibit movement;
A stop located on the sidewall, the stop comprising a structure for promoting the restraint of the second tool, wherein the restraint is partly facilitated by movement of the grinding surface relative to the second tool; It ’s a stop,
C6 tool support further comprising:
[C8]
The plurality of stops are located at different radii from the center of the template within each of the plurality of slots;
C7 tool support.
[C9]
The radius of the second stop is greater than the radius of the first stop by the width of the die being polished;
C8 tool.
[C10]
The width is at least 7 mm;
C9 tool.
[C11]
The height of the side surface is at least 15 mm;
C8 tool.
[C12]
The plurality of slots are positioned around the center of the template such that central openings of the plurality of slots do not face each other;
C8 tool.
[C13]
A method of polishing a die,
Placing a similar template to cover the grinding surface;
Placing a first tool holding a first die to be polished in a first slot of the template such that at least one surface of the first die contacts the grinding surface; Placing a slot region extending radially outward from a central portion of the grinding surface, the first slot region having a sidewall downstream of the first slot;
The friction caused by the grinding surface against the surface of the contacting first die engages a stop mounted on the side wall so as to press the side surface of the first holding tool against the downstream side wall. Removing an external restraint of the template from the first tool so that the grinding surface can be moved relative to the surface of the contacting first die to move Removing the stop closer to the central portion of the grinding surface than the first placed tool;
A method comprising:
[C14]
Removing the first tool from the first slot region while the grinding surface continues to move relative to the support;
The method of C15, further comprising:
[C15]
Returning the first tool to the first slot region while the grinding surface continues to move relative to the support;
The method of C14, further comprising:
[C16]
Placing a second tool holding a second die to be polished in the second slot of the template such that at least one surface of the second die contacts the grinding surface, the second die The slot is horizontally offset from the first slot and extends radially outward from a central portion of the grinding surface, the second slot having a sidewall downstream of the second slot; Placing occurs while the first tool is in intermeshing relationship with the first slot region, and the placing is the friction caused by the grinding surface against the surface of the second contacting die. To move the side surface of the second holding tool against the second downstream side wall and in mesh with a stop mounted on the side wall of the second slot. It possible to move relative to the surface of the die, wherein the grinding surface is in contact of the second, the stop closer to the center of the ground surface than the second, placed tools, placing,
The method of C13, further comprising:
[C17]
The second slot sidewall stop is at a radial distance different from the radial distance of the first slot sidewall;
The method of C16.
[C18]
The different radial distances are a function of the widths of the first and second dies;
The method of C17.
[C19]
Further comprising repeating the last mentioned placing and removing for at least two further slots for polishing the third and fourth dies,
The method of C16.
[C20]
The plurality of slots are located circumferentially around the center of the template, and no two slots are facing each other;
The method of C19.

Claims (20)

An apparatus for smooth polishing of at least one die, comprising:
A template for positioning on a polishing surface, wherein the template comprises at least one slot extending radially outward from the center of the template, the slot being used for polishing a die in parallel to the polishing surface. The slot having at least one side wall extending downward from the template toward the grinding surface when the template is arranged to cover the polishing surface. The side wall extends above the polishing surface and the height is at least equal to the height of the tool used to hold the die; and
At least one stop positioned within the contour of the slot, the stop being stationary in the slot and moving to the polishing surface as the polishing surface moves relative to the positioned die. At least one stop that operates to keep it in contact with, and
A device comprising: The fixture is
At least one additional slot extending radially outward from the center of the template, each of the additional slots being offset circumferentially from another of the plurality of slots. More slots,
Further comprising
Each of the further openings is
At least one sidewall extending downward from the template toward the grinding surface when the template is positioned to cover the grinding surface, the wall having a height “h” above the polishing surface. Elongate, the height “h” being at least one side wall at least equal to the height of the tool used to hold the die;
At least one stop located within the contour of the further slot, the stop being stationary in the further slot and moving the polishing surface while the polishing surface is moving relative to the located die. At least one stop that operates to keep it in contact with
Comprising
The apparatus of claim 1. The plurality of stops of each of the further slots are located at different radial distances within the respective openings;
The apparatus of claim 2. The central openings of each of the further slots are not opposite one another,
The apparatus of claim 2. A splash ablation formed to cover the plurality of slots, the splash ablation having an opening in the center of the housing,
The apparatus of claim 4 further comprising: Die polishing tool support,
An outer edge for temporarily engaging with the grinder;
A template supported by the outer edge portion, wherein the template is held by the outer edge portion above the grinding surface of the grinder with which the outer edge portion is engaged, and the template is an open central portion. portion), and a template
A first slot formed in the template, wherein the slot region extends radially outward from the open central portion toward the outer edge portion, the slot extending from the template above the grinding surface; A first slot having a side wall extending downwardly to a position above the grinder surface that is high enough to inhibit movement of a first die attach tool placed in the first slot. When,
A first stop located on the sidewall at a radius from a center point of the template, the first stop comprising a structure for promoting the suppression of the first tool, wherein the suppression is the first stop; A first stop, partly facilitated by movement of the grinding surface relative to a tool;
Die polishing tool support comprising: A second slot formed in the support, the second slot extending radially outward from the open central portion toward the outer edge portion and horizontally extending from the first slot; The second slot has a side wall portion extending downwardly from the template to a position just above the grinding surface, the side wall of a second die attach tool located in the second slot. A second slot having a height above the grinder surface sufficient to inhibit movement;
A stop located on the sidewall, the stop comprising a structure for promoting the restraint of the second tool, wherein the restraint is partly facilitated by movement of the grinding surface relative to the second tool; It ’s a stop,
The tool support of claim 6 further comprising: The plurality of stops are located at different radii from the center of the template within each of the plurality of slots;
8. Tool support according to claim 7. The radius of the second stop is greater than the radius of the first stop by the width of the die being polished;
The tool of claim 8. The width is at least 7 mm;
The tool of claim 9. The height of the side surface is at least 15 mm;
The tool of claim 8. The plurality of slots are positioned around the center of the template such that central openings of the plurality of slots do not face each other;
The tool of claim 8. A method of polishing a die,
Placing a similar template to cover the grinding surface;
Placing a first tool holding a first die to be polished in a first slot of the template such that at least one surface of the first die contacts the grinding surface; Placing a slot region extending radially outward from a central portion of the grinding surface, the first slot region having a sidewall downstream of the first slot;
The friction caused by the grinding surface against the surface of the contacting first die engages a stop mounted on the side wall so as to press the side surface of the first holding tool against the downstream side wall. Removing an external restraint of the template from the first tool so that the grinding surface can be moved relative to the surface of the contacting first die to move Removing the stop closer to the central portion of the grinding surface than the first placed tool;
A method comprising: Removing the first tool from the first slot region while the grinding surface continues to move relative to the support;
16. The method of claim 15, further comprising: Returning the first tool to the first slot region while the grinding surface continues to move relative to the support;
15. The method of claim 14, further comprising: Placing a second tool holding a second die to be polished in the second slot of the template such that at least one surface of the second die contacts the grinding surface, the second die The slot is horizontally offset from the first slot and extends radially outward from a central portion of the grinding surface, the second slot having a sidewall downstream of the second slot; Placing occurs while the first tool is in intermeshing relationship with the first slot region, and the placing is the friction caused by the grinding surface against the surface of the second contacting die. To move the side surface of the second holding tool against the second downstream side wall and in mesh with a stop mounted on the side wall of the second slot. It possible to move relative to the surface of the die, wherein the grinding surface is in contact of the second, the stop closer to the center of the ground surface than the second, placed tools, placing,
14. The method of claim 13, further comprising: The second slot sidewall stop is at a radial distance different from the radial distance of the first slot sidewall;
The method of claim 16. The different radial distances are a function of the widths of the first and second dies;
The method of claim 17. Further comprising repeating the last mentioned placing and removing for at least two further slots for polishing the third and fourth dies,
The method of claim 16. The plurality of slots are located circumferentially around the center of the template, and no two slots are facing each other;
The method of claim 19.

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